科学家发现了感染一种逆转录病毒与前列腺癌之间的强有力的联系，每6位美国男性就有1位患有前列腺癌。该研究可能为开发新的诊断标记提供机会，而且有潜力用抗逆转录病毒疗法或者疫苗预防或治疗前列腺癌，这种方法已经用于常常导致宫颈癌的人类乳头瘤病毒。近来的研究在前列腺癌中发现了异嗜性鼠白血病病毒相关病毒（XMRV） ，并且发现了携带一种特定遗传变异的人类男性亚群更容易受到病毒的感染。
Ila Singh及其同事检查了300个前列腺癌标本，结果在超过1/4的样本中发现了XMRV。这组科学家报告说，这种病毒更可能出现在更具侵略性的癌症中，而且病毒蛋白出现在了癌细胞中，这提示XMRV感染可能与肿瘤形成有直接的联系。感染的发生独立于RNase L基因的变种——这一发现把“面临风险”的人群从一小群遗传易感人群扩展到了所有男性。根据XMRV的外观、序列比较，以及与其他已知逆转录病毒的相似性，这组科学家把这种病毒归为γ逆转录病毒。这一病毒属的成员已知会导致许多动物的白血病和肉瘤，但是此前尚未被证明能导致人类癌症。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS September 8, 2009, doi: 10.1073/pnas.0906922106
XMRV is present in malignant prostatic epithelium and is associated with prostate cancer, especially high-grade tumors
Robert Schlaberga,1, Daniel J. Choeb, Kristy R. Browna, Harshwardhan M. Thakerb and Ila R. Singha,b,2
aDepartment of Pathology and Cell Biology, Columbia University Medical Center, 622 West 168th Street, New York, NY 10032; and
bDepartment of Pathology, University of Utah, Emma Eccles Jones Medical Research Building, 15 North Medical Drive East, Salt Lake City, UT 84112
Xenotropic murine leukemia virus–related virus (XMRV) was recently discovered in human prostate cancers and is the first gammaretrovirus known to infect humans. While gammaretroviruses have well-characterized oncogenic effects in animals, they have not been shown to cause human cancers. We provide experimental evidence that XMRV is indeed a gammaretrovirus with protein composition and particle ultrastructure highly similar to Moloney murine leukemia virus (MoMLV), another gammaretrovirus. We analyzed 334 consecutive prostate resection specimens, using a quantitative PCR assay and immunohistochemistry (IHC) with an anti-XMRV specific antiserum. We found XMRV DNA in 6% and XMRV protein expression in 23% of prostate cancers. XMRV proteins were expressed primarily in malignant epithelial cells, suggesting that retroviral infection may be directly linked to tumorigenesis. XMRV infection was associated with prostate cancer, especially higher-grade cancers. We found XMRV infection to be independent of a common polymorphism in the RNASEL gene, unlike results previously reported. This finding increases the population at risk for XMRV infection from only those homozygous for the RNASEL variant to all individuals. Our observations provide evidence for an association of XMRV with malignant cells and with more aggressive tumors.
